Catalyzed additions of allylamines to alkoxyhydrosilanes are known methods for preparation of aminopropylalkoxysilanes. Of the known catalysts platinum catalysts have been shown to be the most useful for these reactions. These platinum-catalyzed reactions produce both gamma- and beta-isomers of the final product, e.g., a gamma- to beta-isomer ratio of up to about 15:1 has been described in U.S. Pat. No. 4,481,364. Since the gamma-isomer is the desirable isomer, the beta-isomer must be removed to obtain a relatively pure (&gt;95%) product of the gamma-isomer. It would, therefore, be desirable to utilize a hydrosilation process which would effectively increase the ratio of gamma- to beta-isomer of the final product (e.g. the ratio of gamma-aminopropyltriethoxysilane to beta-aminopropyltriethoxysilane).
Accordingly, it is an object of this invention to provide a method for significantly increasing the gamma- to beta- isomer ratio of the final product of the addition of allylamines to alkoxyhydrosilanes.